Efficient Ni-Mo hydrodesulfurization catalyst prepared through Keggin polyoxometalate

Abstract

NiMo/SiO2 hydrodesulfurization catalyst prepared through the polyoxometalate route using Keggin type phosphomolybdates has high activity in HDS of thiophene at 350-400°C and 1bar pressure. The NiMo/SiO2 pre-catalyst retains intact Keggin structure of phosphomolybdic polyoxometalate, which transforms on stream into a NiMo sulfidic active phase. The pre-catalyst also possesses Brønsted and Lewis acidity, which is lost during the HDS reaction. This catalyst undergoes faster sulfidation and shows higher thiophene conversion and higher butene selectivity than conventional industrial NiMo/Al2O3 catalyst with similar Mo loading. The polyoxometalate catalyst preparation route is therefore considered to be a performance enhancement methodology for HDS catalysis.